The Captain Lacey Mysteries is an absolutely riveting series of books set during the Regency era. Gabriel Lacey's adventures to date mainly take place in London, except book 4, The Sudbury School Murders, which is (mostly) set in Berkshire
Ashley Gardner is a pseudonym of Jennifer Ashley, an incredibly talented author who I think is American, but she has lived all over the world, and is currently residing in Arizona. In any case, I am sure she is not British, but her knowledge and descriptions of Regency London keep me totally enthralled. Her descriptions of the London streets, whether they be in Mayfair or the 7Dials are amazingly detailed, and if any of it just her imagination, rather than fact, no one would know because her narratives, as told us from Captain Lacey's, first person POV, are so rich in detail, I find myself spellbound. I am pretty sure, however, that Ashley has spent eons doing research and actually walking the streets of London and as a result of this hard work, the reader will find him/herself transported back to the Regency era.
The mysteries are interesting enough to make you want to immediately go out and buy the next book in the series. Gabriel Lacey has a fairly large contingent of friends, acquaintances and the odd enemy and the character development of all these people and their relationships with each other is just as enthralling for me as the mysteries themselves. Captain Lacey is a complex character who is far from perfect, but he is always a gentleman and he is always a champion of the downtrodden. He usually comes down on the side of law and order, but he does have a temper that would surely get him into trouble if he did not have friends in high places.
If you want to make these books even more unputdownable and you subscribe to Audible.com.au, then I recommend that you use the whispersync feature and buy the audible narration to accompany the written word. James Gillies brings Gabriel Lacey and all the other characters to vivid life; his accents are amazingly diverse and fabulously entertaining.
The books are all available through Audible.com.au but using the whispersync feature allows you to buy the audible addition at a much cheaper rate.
I know I have not said anything specific about a Covent Garden Mystery, but know that it is a hugely entertaining book, and if you have not read the previous 5 in the series, I recommend that you start at the beginning.